Can not connect any more e-mail accounts to iPhone

Hello,

I have previously successfully added newly created accounts to my iPhone e-mail.
I followed the instructions from here: https://www.zoho.eu/mail/help/idevice-access.html
and I was able to set up 2 accounts. I have now though created some time after another account but always receive this message " The username or password for "imap.zoho.eu" is incorrect. I have verified everything several times but still get this messages over and over again which before was never the case.
If I cancel the message and click on "Next" I am prompted with a message saying "This account may not be able to send or receive emails. Are you sure you want to save?" which I don't do as I need this account to send and receive emails.

How can I fix this issue?

Many thanks in advance!